When one makes an unintentional posting error on Facebook. Derived from FACEbook + brainFART.
Man, I had a serious Facefart today--while posting to my gf's wall about how to properly execute a dirty sanchez, I accidentially posted to Mom's!
when a man/woman farts into the face of a man/woman for sexual or humiliation reasons.
i think i will facefart him in the bathroom.
i facefarted her in bed last night.